Flash an error on save when required fields are missed

- Add error type constants
- Flash an error message when the user saves without completing all required fields
- Surface presence errors

.all-contributorsrc

@@ -373,6 +373,15 @@
       "contributions": [
         "doc"
       ]
+    },
+    {
+      "login": "aquibm",
+      "name": "Aquib Master",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/2936813?v=4",
+      "profile": "http://aquibm.com/",
+      "contributions": [
+        "code"
+      ]
     }
   ]
 }

README.md

@@ -1,5 +1,5 @@
 # Netlify CMS
-[![All Contributors](https://img.shields.io/badge/all_contributors-47-orange.svg?style=flat-square)](#contributors)
+[![All Contributors](https://img.shields.io/badge/all_contributors-48-orange.svg?style=flat-square)](#contributors)
 
 A CMS for static site generators. Give non-technical users a simple way to edit
 and add content to any site built with a static site generator.
@@ -54,7 +54,7 @@ Thanks goes to these wonderful people ([emoji key](https://github.com/kentcdodds
 | [<img src="https://avatars3.githubusercontent.com/u/1923476?v=4" width="100px;"/><br /><sub>Kalin Chernev</sub>](https://github.com/kalinchernev)<br /> | [<img src="https://avatars2.githubusercontent.com/u/5018268?v=4" width="100px;"/><br /><sub>tortilaman</sub>](https://github.com/tortilaman)<br /> | [<img src="https://avatars0.githubusercontent.com/u/1184334?v=4" width="100px;"/><br /><sub>Václav Klecanda</sub>](http://www.vxk.cz)<br /> | [<img src="https://avatars0.githubusercontent.com/u/2983665?v=4" width="100px;"/><br /><sub>DrianHillman</sub>](http://drianhillman.me)<br /> | [<img src="https://avatars1.githubusercontent.com/u/1198032?v=4" width="100px;"/><br /><sub>Sean Crawford</sub>](https://github.com/seantcoyote)<br /> | [<img src="https://avatars1.githubusercontent.com/u/111932?v=4" width="100px;"/><br /><sub>Robert Riemann</sub>](http://blog.riemann.cc)<br /> | [<img src="https://avatars1.githubusercontent.com/u/4165105?v=4" width="100px;"/><br /><sub>Ben Berman</sub>](http://jygabyte.com)<br /> |
 | [<img src="https://avatars3.githubusercontent.com/u/4349324?v=4" width="100px;"/><br /><sub>Benjamin Kniffler</sub>](https://github.com/bkniffler)<br /> | [<img src="https://avatars1.githubusercontent.com/u/845983?v=4" width="100px;"/><br /><sub>Mike Wickett</sub>](http://www.wickett.ca)<br /> | [<img src="https://avatars1.githubusercontent.com/u/2751799?v=4" width="100px;"/><br /><sub>Rory Claasen</sub>](http://roryclaasen.me)<br /> | [<img src="https://avatars3.githubusercontent.com/u/724844?v=4" width="100px;"/><br /><sub>Frederic Brodbeck</sub>](http://www.freder.io/)<br /> | [<img src="https://avatars2.githubusercontent.com/u/1245746?v=4" width="100px;"/><br /><sub>Stuart Dum</sub>](https://github.com/simplystuart)<br /> | [<img src="https://avatars0.githubusercontent.com/u/8184251?v=4" width="100px;"/><br /><sub>Ryan Watters</sub>](https://github.com/rdwatters)<br /> | [<img src="https://avatars3.githubusercontent.com/u/4315?v=4" width="100px;"/><br /><sub>Helder S Ribeiro</sub>](https://twitter.com/hsribei)<br /> |
 | [<img src="https://avatars1.githubusercontent.com/u/979966?v=4" width="100px;"/><br /><sub>Artem Govorov</sub>](http://dm.gl)<br /> | [<img src="https://avatars3.githubusercontent.com/u/2683300?v=4" width="100px;"/><br /><sub>Cédric Delpoux</sub>](http://xuopled.netlify.com/)<br /> | [<img src="https://avatars3.githubusercontent.com/u/83225?v=4" width="100px;"/><br /><sub>imorente</sub>](https://github.com/imorente)<br /> | [<img src="https://avatars3.githubusercontent.com/u/5230460?v=4" width="100px;"/><br /><sub>David Francoeur</sub>](http://davidfrancoeur.com)<br /> | [<img src="https://avatars3.githubusercontent.com/u/1954977?v=4" width="100px;"/><br /><sub>Rusta</sub>](https://github.com/Rusta)<br /> | [<img src="https://avatars1.githubusercontent.com/u/1299786?v=4" width="100px;"/><br /><sub>Henrik Lau Eriksson</sub>](http://henrik.laueriksson.com)<br /> | [<img src="https://avatars0.githubusercontent.com/u/1294877?v=4" width="100px;"/><br /><sub>Kraig Walker</sub>](https://www.kraigwalker.com)<br /> |
-| [<img src="https://avatars1.githubusercontent.com/u/2994311?v=4" width="100px;"/><br /><sub>Rich Cook</sub>](http://www.TalesofMurder.com)<br /> | [<img src="https://avatars3.githubusercontent.com/u/1309950?v=4" width="100px;"/><br /><sub>Damien Van Der Windt</sub>](https://github.com/damienvdw)<br /> | [<img src="https://avatars2.githubusercontent.com/u/1571899?v=4" width="100px;"/><br /><sub>Matt Jared</sub>](http://mattjared.github.io/)<br /> | [<img src="https://avatars1.githubusercontent.com/u/1100280?v=4" width="100px;"/><br /><sub>bruce-one</sub>](https://github.com/bruce-one)<br /> | [<img src="https://avatars3.githubusercontent.com/u/103008?v=4" width="100px;"/><br /><sub>Frank Taillandier</sub>](https://frank.taillandier.me)<br />[📖](https://github.com/netlify/netlify-cms/commits?author=DirtyF "Documentation") |
+| [<img src="https://avatars1.githubusercontent.com/u/2994311?v=4" width="100px;"/><br /><sub>Rich Cook</sub>](http://www.TalesofMurder.com)<br /> | [<img src="https://avatars3.githubusercontent.com/u/1309950?v=4" width="100px;"/><br /><sub>Damien Van Der Windt</sub>](https://github.com/damienvdw)<br /> | [<img src="https://avatars2.githubusercontent.com/u/1571899?v=4" width="100px;"/><br /><sub>Matt Jared</sub>](http://mattjared.github.io/)<br /> | [<img src="https://avatars1.githubusercontent.com/u/1100280?v=4" width="100px;"/><br /><sub>bruce-one</sub>](https://github.com/bruce-one)<br /> | [<img src="https://avatars3.githubusercontent.com/u/103008?v=4" width="100px;"/><br /><sub>Frank Taillandier</sub>](https://frank.taillandier.me)<br />[📖](https://github.com/netlify/netlify-cms/commits?author=DirtyF "Documentation") | [<img src="https://avatars0.githubusercontent.com/u/2936813?v=4" width="100px;"/><br /><sub>Aquib Master</sub>](http://aquibm.com/)<br />[💻](https://github.com/netlify/netlify-cms/commits?author=aquibm "Code") |
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 
 This project follows the [all-contributors](https://github.com/kentcdodds/all-contributors) specification. Contributions of any kind welcome!

src/actions/entries.js

@@ -7,6 +7,7 @@ import { getIntegrationProvider } from '../integrations';
 import { getAsset, selectIntegration } from '../reducers';
 import { selectFields } from '../reducers/collections';
 import { createEntry } from '../valueObjects/Entry';
+import ValidationErrorTypes from '../constants/validationErrorTypes';
 
 const { notifSend } = notifActions;
 
@@ -265,9 +266,23 @@ export function persistEntry(collection) {
   return (dispatch, getState) => {
     const state = getState();
     const entryDraft = state.entryDraft;
+    const fieldsErrors = entryDraft.get('fieldsErrors');
 
     // Early return if draft contains validation errors
-    if (!entryDraft.get('fieldsErrors').isEmpty()) return Promise.reject();
+    if (!fieldsErrors.isEmpty()) {
+      const hasPresenceErrors = fieldsErrors
+        .some(errors => errors.some(error => error.type && error.type === ValidationErrorTypes.PRESENCE));
+      
+      if (hasPresenceErrors) {
+        dispatch(notifSend({
+          message: 'Oops, you\'ve missed a required field. Please complete before saving.',
+          kind: 'danger',
+          dismissAfter: 8000,
+        }));
+      }
+
+      return Promise.reject();
+    }
 
     const backend = currentBackend(state.config);
     const assetProxies = entryDraft.get('mediaFiles').map(path => getAsset(state, path));

src/components/ControlPanel/ControlPane.js

@@ -37,9 +37,11 @@ export default class ControlPane extends Component {
         <label className={labelClass} htmlFor={fieldName}>{field.get('label')}</label>
         <ul className="nc-controlPane-errors">
           {
-            errors && errors.map(error => (
+            errors && errors.map(error =>
-              typeof error === 'string' && <li key={error.trim().replace(/[^a-z0-9]+/gi, '-')}>{error}</li>
+              error.message &&
-            ))
+              typeof error.message === 'string' &&
+              <li key={error.message.trim().replace(/[^a-z0-9]+/gi, '-')}>{error.message}</li>
+            )
           }
         </ul>
         <ControlHOC 

src/components/Widgets/ControlHOC.js

@@ -1,6 +1,7 @@
 import PropTypes from 'prop-types';
 import React, { Component } from 'react';
 import ImmutablePropTypes from "react-immutable-proptypes";
+import ValidationErrorTypes from '../../constants/validationErrorTypes';
 
 const truthy = () => ({ error: false });
 
@@ -57,7 +58,12 @@ class ControlHOC extends Component {
       (value.hasOwnProperty('length') && value.length === 0) ||
       (value.constructor === Object && Object.keys(value).length === 0)
     )) {
-      return { error: true };
+      const error = {
+        type: ValidationErrorTypes.PRESENCE,
+        message: `${ field.get('label', field.get('name')) } is required.`,
+      };
+
+      return { error };
     }
     return { error: false };
   }
@@ -65,8 +71,14 @@ class ControlHOC extends Component {
   validatePattern(field, value) {
     const pattern = field.get('pattern', false);
     if (pattern && !RegExp(pattern.first()).test(value)) {
-      return { error: `${ field.get('label', field.get('name')) } didn't match the pattern: ${ pattern.last() }` };
+      const error = {
+        type: ValidationErrorTypes.PATTERN,
+        message: `${ field.get('label', field.get('name')) } didn't match the pattern: ${ pattern.last() }`,
+      };
+
+      return { error };
     }
+
     return { error: false };
   }
 
@@ -80,11 +92,22 @@ class ControlHOC extends Component {
     } else if (response instanceof Promise) {
       response.then(
         () => { this.validate({ error: false }); },
-        (error) => { 
+        (err) => { 
-          this.validate({ error: `${ field.get('label', field.get('name')) } - ${ error }.` });
+          const error = {
+            type: ValidationErrorTypes.CUSTOM,
+            message: `${ field.get('label', field.get('name')) } - ${ err }.`,
+          };
+
+          this.validate({ error });
         }
       );
-      return { error: `${ field.get('label', field.get('name')) } is processing.` };
+
+      const error = {
+        type: ValidationErrorTypes.CUSTOM,
+        message: `${ field.get('label', field.get('name')) } is processing.`,
+      };
+
+      return { error };
     }
     return { error: false };
   };

src/constants/validationErrorTypes.js

@@ -0,0 +1,5 @@
+export default {
+  PRESENCE: 'PRESENCE',
+  PATTERN: 'PATTERN',
+  CUSTOM: 'CUSTOM',
+};